table.rb in amqp-client-1.0.1

- old
+ new
@@ -1,123 +1,134 @@
 # frozen_string_literal: true
 
 module AMQP
-  # Encode/decode AMQP Tables
-  module Table
-    module_function
+  class Client
+    # Encode and decode an AMQP table to/from hash, only used internally
+    # @api private
+    module Table
+      module_function
 
-    def encode(hash)
-      tbl = ""
-      hash.each do |k, v|
-        key = k.to_s
-        tbl += [key.bytesize, key, encode_field(v)].pack("C a* a*")
+      # Encodes a hash into a byte array
+      # @return [String] Byte array
+      def encode(hash)
+        tbl = StringIO.new
+        hash.each do |k, v|
+          key = k.to_s
+          tbl.write [key.bytesize, key].pack("Ca*")
+          tbl.write encode_field(v)
+        end
+        tbl.string
       end
-      tbl
-    end
 
-    def decode(bytes)
-      h = {}
-      pos = 0
-
-      while pos < bytes.bytesize
-        key_len = bytes[pos].ord
-        pos += 1
-        key = bytes.byteslice(pos, key_len).force_encoding("utf-8")
-        pos += key_len
-        rest = bytes.byteslice(pos, bytes.bytesize - pos)
-        len, value = decode_field(rest)
-        pos += len + 1
-        h[key] = value
+      # Decodes an AMQP table into a hash
+      # @return [Hash<String, Object>]
+      def decode(bytes)
+        hash = {}
+        pos = 0
+        while pos < bytes.bytesize
+          key_len = bytes[pos].ord
+          pos += 1
+          key = bytes.byteslice(pos, key_len).force_encoding("utf-8")
+          pos += key_len
+          rest = bytes.byteslice(pos, bytes.bytesize - pos)
+          len, value = decode_field(rest)
+          pos += len + 1
+          hash[key] = value
+        end
+        hash
       end
-      h
-    end
 
-    def encode_field(value)
-      case value
-      when Integer
-        if value > 2**31
-          ["l", value].pack("a q>")
-        else
-          ["I", value].pack("a l>")
+      # Encoding a single value in a table
+      # @api private
+      def encode_field(value)
+        case value
+        when Integer
+          if value > 2**31
+            ["l", value].pack("a q>")
+          else
+            ["I", value].pack("a l>")
+          end
+        when Float
+          ["d", value].pack("a G")
+        when String
+          ["S", value.bytesize, value].pack("a L> a*")
+        when Time
+          ["T", value.to_i].pack("a Q>")
+        when Array
+          bytes = value.map { |e| encode_field(e) }.join
+          ["A", bytes.bytesize, bytes].pack("a L> a*")
+        when Hash
+          bytes = Table.encode(value)
+          ["F", bytes.bytesize, bytes].pack("a L> a*")
+        when true
+          ["t", 1].pack("a C")
+        when false
+          ["t", 0].pack("a C")
+        when nil
+          ["V"].pack("a")
+        else raise ArgumentError, "unsupported table field type: #{value.class}"
         end
-      when Float
-        ["d", value].pack("a G")
-      when String
-        ["S", value.bytesize, value].pack("a L> a*")
-      when Time
-        ["T", value.to_i].pack("a Q>")
-      when Array
-        bytes = value.map { |e| encode_field(e) }.join
-        ["A", bytes.bytesize, bytes].pack("a L> a*")
-      when Hash
-        bytes = Table.encode(value)
-        ["F", bytes.bytesize, bytes].pack("a L> a*")
-      when true
-        ["t", 1].pack("a C")
-      when false
-        ["t", 0].pack("a C")
-      when nil
-        ["V"].pack("a")
-      else raise "unsupported table field type: #{value.class}"
       end
-    end
 
-    # returns [length of field including type, value of field]
-    def decode_field(bytes)
-      type = bytes[0]
-      pos = 1
-      case type
-      when "S"
-        len = bytes.byteslice(pos, 4).unpack1("L>")
-        pos += 4
-        [4 + len, bytes.byteslice(pos, len).force_encoding("utf-8")]
-      when "F"
-        len = bytes.byteslice(pos, 4).unpack1("L>")
-        pos += 4
-        [4 + len, decode(bytes.byteslice(pos, len))]
-      when "A"
-        len = bytes.byteslice(pos, 4).unpack1("L>")
-        a = []
-        while pos < len
-          length, value = decode_field(bytes.byteslice(pos, -1))
-          pos += length + 1
-          a << value
+      # Decodes a single value
+      # @return [Array<Integer, Object>] Bytes read and the parsed object
+      # @api private
+      def decode_field(bytes)
+        type = bytes[0]
+        pos = 1
+        case type
+        when "S"
+          len = bytes.byteslice(pos, 4).unpack1("L>")
+          pos += 4
+          [4 + len, bytes.byteslice(pos, len).force_encoding("utf-8")]
+        when "F"
+          len = bytes.byteslice(pos, 4).unpack1("L>")
+          pos += 4
+          [4 + len, decode(bytes.byteslice(pos, len))]
+        when "A"
+          len = bytes.byteslice(pos, 4).unpack1("L>")
+          a = []
+          while pos < len
+            length, value = decode_field(bytes.byteslice(pos, -1))
+            pos += length + 1
+            a << value
+          end
+          [4 + len, a]
+        when "t"
+          [1, bytes[pos].ord == 1]
+        when "b"
+          [1, bytes.byteslice(pos, 1).unpack1("c")]
+        when "B"
+          [1, bytes.byteslice(pos, 1).unpack1("C")]
+        when "s"
+          [2, bytes.byteslice(pos, 2).unpack1("s")]
+        when "u"
+          [2, bytes.byteslice(pos, 2).unpack1("S")]
+        when "I"
+          [4, bytes.byteslice(pos, 4).unpack1("l>")]
+        when "i"
+          [4, bytes.byteslice(pos, 4).unpack1("L>")]
+        when "l"
+          [8, bytes.byteslice(pos, 8).unpack1("q>")]
+        when "f"
+          [4, bytes.byteslice(pos, 4).unpack1("g")]
+        when "d"
+          [8, bytes.byteslice(pos, 8).unpack1("G")]
+        when "D"
+          scale = bytes[pos].ord
+          pos += 1
+          value = bytes.byteslice(pos, 4).unpack1("L>")
+          d = value / 10**scale
+          [5, d]
+        when "x"
+          len = bytes.byteslice(pos, 4).unpack1("L>")
+          [4 + len, bytes.byteslice(pos, len)]
+        when "T"
+          [8, Time.at(bytes.byteslice(pos, 8).unpack1("Q>"))]
+        when "V"
+          [0, nil]
+        else raise ArgumentError, "unsupported table field type: #{type}"
         end
-        [4 + len, a]
-      when "t"
-        [1, bytes[pos].ord == 1]
-      when "b"
-        [1, bytes.byteslice(pos, 1).unpack1("c")]
-      when "B"
-        [1, bytes.byteslice(pos, 1).unpack1("C")]
-      when "s"
-        [2, bytes.byteslice(pos, 2).unpack1("s")]
-      when "u"
-        [2, bytes.byteslice(pos, 2).unpack1("S")]
-      when "I"
-        [4, bytes.byteslice(pos, 4).unpack1("l>")]
-      when "i"
-        [4, bytes.byteslice(pos, 4).unpack1("L>")]
-      when "l"
-        [8, bytes.byteslice(pos, 8).unpack1("q>")]
-      when "f"
-        [4, bytes.byteslice(pos, 4).unpack1("g")]
-      when "d"
-        [8, bytes.byteslice(pos, 8).unpack1("G")]
-      when "D"
-        scale = bytes[pos].ord
-        pos += 1
-        value = bytes.byteslice(pos, 4).unpack1("L>")
-        d = value / 10**scale
-        [5, d]
-      when "x"
-        len = bytes.byteslice(pos, 4).unpack1("L>")
-        [4 + len, bytes.byteslice(pos, len)]
-      when "T"
-        [8, Time.at(bytes.byteslice(pos, 8).unpack1("Q>"))]
-      when "V"
-        [0, nil]
-      else raise "unsupported table field type: #{type}"
       end
     end
   end
 end